In 1989, the Japan Teachers' Union, Nikkyoso, split into two unions after 2 years of factional infighting. Japan has two political camps, the governing conservative Liberal Democratic Party and the left-wing Japan Socialist Party. The teachers' union is a powerful member in the camp of the latter. This book incorporates studies of the links between the union and other political and administrative institutions and examines Nikkyoso's place in the whole Japanese political system, while considering the ideologies and group dynamics within the union. Data were gathered from official journals, newsletters, or publications. Detailed interviews of bureaucrats, union officials, and classroom teachers were conducted in Tokyo and the Saitama and Auchi prefectures. The first two chapters cover the history of the union. The schism itself is examined in chapter 3. Chapter 4 is concerned with power relations within the national education system. Chapter 5 examines the debate on education reform. Chapter 6 considers the union within the context of postwar public-sector unionism in Japan and compares it with other teacher unions around the world. In chapter 6, the connections between the decline of Nikkyoso and the decline of the Japan Socialist Party are examined, along with possible future consequences. (Contains 251 references.) (RKJ)